Real Soon Now I will be mounting a stock oil bath air cleaner on the Wonderbus (71). I'm trying to sort out how that thing works and how it is meant to be connected.
First, there are a couple of hose inlets on it, about 1/2'' (12mm) in diameter. Looking at illustrations in Bentley's 1968-1979 Bus book, I see that one is for a hose that goes to the activated charcoal filter, the other side of which is connected to the fan housing via a hose. It's not clear to me what function in life this setup is meant to have. The other inlet on the air cleaner is, I think, for a hose coming from the gas tank. This performs an evaporative emission control function.
Both inlets enter the air cleaner at points where they would mix with the cleaner's incoming air stream, to be cleaned along with the main incoming air. The PO removed the charcoal canister, and there is no sign of a gas tank hose. So I reckon I should plug these two inlets on the air cleaner. Yes/no?
Second, I see two main intakes for the cleaner. The upper one is long and pointy, and there is a shorter, fatter, cylindrical one slung under it. I also see some kind of flapper valve with a counterweight, and a spring thing which Bentley's describes as a thermostat for the intake air preheating valve. Is something meant to be connected to that lower intake?